Well-drilling tool of the rotary type



Doc. 1930- 'c. B. KENNEDYE 1;786,413

WELL DRILLING OF THE ROTARY TYPE Filed Feb, 2, 1925 x ZA/L/EA/TQ r97 TOIENE Y Patented Dec. 23, 1 930 UNITED, s'r 'ras PATENT oat-1e11,;

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Many difiiculties have been experienced in drilling wells of relatively great epth. For.

through formations of varying degrees of dull and do not drill a hole of uniform diameter. Or, a hard spot in the formation may force the drill out of vertical line, producing a kink in theside walls of the hole. Or, a projecting stone loosened by'the drill may.protrude inwardly beyond the periphery of the hole, causing the casing,fwhen lowered into lace, to stick and bind. Very frequent y, (proper placement of the casin' is prevents because the walls of the dr1 led ole are neither smooth nor exactly vertical. These difiiculties and conditions require that the casing be raised and withdrawn to permit reamin of the hole to proper size to allow the caslng to be lowered into place. Also, the bits must be withdrawn to permit resharpening.

To obviate these time-consuming andexpensive steps, I have devised, and my invention has for a primary object, the provision of a well-drilling tool comprising drilling and reaming bits of novel construction for the economical and efiicient accomplishment of the dual operations of drilling and reaming at the same time. T

My invention has for another object the provision of a tool of the t pe stated comprising a body or stock an 'a plurality of etachable bits that may be readily and conveniently removed and replaced. The stock and bits are so constructedthat the bits, when hel against accidental displacement.

Mylnvention has for a still further object the provision of a tool of such construction that water under pressure is discharged directly u on the cutting edges of the bits and 'upon t e bottom of the hole being drilled with the result that the drilling of the well is reatly facilitated. Y

y invention has for a still further object the im rovement of rotarwell-drilling tools. .1 In t e accompanying rawing, Fig. 1 is a view, partly in elevation and partly in longitudinal section, of a rotary well-drilling tool embodying my invention. 7

its greatest diameter. From strength, durability, an

in operative position, are firmly and securely Fig. 2 is an enlarged transverse sectional view of the'tool taken approximately 011 the dinal sectional view of the tool, and" Figs. 4 and 5 are detail sectional views of the tool taken respectively, on the lines 44 and'5-5 of ig. 3. Y a

Referring 'more in detail to, the drawin A designates the body orstock of the too which 1s constructed of suitable metal and is of'suitable weight and dimensions. Body A, at a point 1 intermediate its ends, has I its lower end it is longitudina y cut-away upon opposite sides to form opposed faces 2, sinuous in surface contour transversely of the stock in simulation of the tail of a fish.

From intermediate point 1, the body A is extended. upwardly and may be provided with an integral extension 3Iter'minating in a threaded socket 4 adapted to receive the threaded end of the drill-tubing "(not showngl. The full strength of the bit-stock A is t ereby retained, and thus, the-use of a separate drill-collar, with its inherent rtion 1 tov weaknesses is obviated; sharp comers in the I bpdy and jumping of pins are eliminated,

and tendency toward fractures in the body A is reduced .to a minimum. Such construction also obviates breaking'of the bit-stock at the oint of connection with the separate drill-co ar thus greatly increasing the. ,efliciency of the tool.

Opening to o positesides of the stock A Also formed in and disposed at the lower end of the stock A, is a pair of cross-slots '11. The slots 11 open to the lower end and to sides of the stock A' and are in communication with the respective slots 7. The slots llmay be disposed obliquely to the longitudinal axis of stock A and may extend lnwardly from opposite sides to somewhat and extending ownwardly from the intermediateportion 1 are slots 7. Each slot is ed or arcuated from the outer lower corner 15 to its inner lower corner 16. In use, the concave Surfaces of the cutting ends 14 are disposed on the side of the direction of rotation; their longitudinal axes are parallel, but off-set, corresponding to the obliguely disposed, overlapping arrangement 0 the slots 11, the contour of the lower cutting ends 13 and their cutting edges 14 completing the resemblance of the stock A and bits B to a fish-tail.

Similarl removabl fitting in and adapted for endwise slida 1e accommodation in the slots or ways 7, are individual reamingbits C, having preferably the outer and crosssectional contour best seen in Figs. 2 and 4. Each bit C comprises a suitably elongated substantially rectangular body 17 gently rounded upon its outer face 18, and provided longitudinally at its inner side with tongues 19 for reamer retaining engagement with the grooves 8 at the base of the slots 7. Upon their inner faces and adjacent their upper ends, the bits C are rovided with spring members 20 adapted or disposition within the recesses '9 and for engagement with the recess-shoulders 10 for removably or detachably locking-the bits G from endwise upward displacement in the slots 7. In passln I may say that, by means of a suitable tool not shown) projected through a suitable channel or way 21 in stock A,'the s rings 20 may be depressed and disengaged rom shoulders 10 to permit endwise removal of the b1ts C. Each bit C may be cut away at its lower end, as at 22, for interengaging with the cooperativel cut-away outer corner 23 of the adj acent rilling-bit B for releasably locking the bit B from sidewise removal from its slot 11.

Formed in approximately the longitudinal center of the body A is a water duct or channel 24, which duct extends from the upper end of stock A, where it is in open communication with an inlet channel 25 in the tubing 5, to a point 26 adjacent the slots 11, where channel 24 divides into oppositely disposed branch ducts 27, opening on the outer surface of stock A and terminating in longitudinal surface grooves 28, for conducting the discharging water directly upon the drilling bits B, thus flushing said bits and keeping them clean. It will be understood that water under considerable head is forced along the cutting surfaces of the drilling bits B, and upon the bottom of the hole being drilled, in such a manner as to remove loose matter from the well, and also to keep the bits B substantially free from accumulated dirt, stone-dust and the like.

In use and operation, the drilling-bits B are first placed in the slots 11. The reaming bits 0 are then slidably disposed in slots 7, the bits C interengaging at their lower ends 22 with the upper outer corners 23 of bits B, the springs 20 interlocking with the shoulders 10. The reamers C are thus efiiciently locked against endwise displacement and the bits B, in turn, are securely held by the reamers C from sidewise displacement, the wedgelike engagement between bits B and stock A, securely retaining bits B from edgewise separation from the stock. It will be evident, however, that, by disengagement of springs 20 from the recess-shoulders 10, reamers C may be slidably removed from slots 7; the bits B, in turn, may be conveniently removed from slots 11, both reamers C and bits B being then readily repaired or replaced as conditions may require.

It will be observed that the en agement of the drilling-bits B rovides a sufiiclent hearing surface to enab e bits B to withstand the weight imposed by stock A and drill-tub ing 5.

In practice the bits B extend outwardly beyond stock A and slightly beyond the arcuated faces 18 of the reaming-bits C, formin straight lines parallel with the longitudina axis of the stock A. Thus, the diameter of the hole being drilled is uniformly maintained. The outer faces 18 of reamers C present no cutting edge and efliciently function in the rotary actuations of stock A in smoothing and straighteningthe walls of the hole being drilled.

Thus, by means of my new tool, both reaming and drilling operations may be accomplished and effected at the same time. Both reaming and drilling bits may be inexpensively repaired or replaced. I ma add that my new tool has been found excee ingly eflicient in use and operation; it is relatively inexpensive in maintenance; it facilitates, and largely reduces the cost of, well drilling, and it accomplishes fully the objects and purposes hereinbefore stated.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

A well-drilling tool, including, in combination, a head having a point of greatest cross section intermediate its ends and longitudinally decreasing in cross section from that point to its lower end, and sinuous in surface contour in simulation of the tail of a fish slots transversely disposed at the lower end of said head, drilling elements removably mounted in said slots, elongated slots in the side of said head, reamers adapted to be removably mounted in the elongated slots having surfaces projecting beyond the sides of said head, said reamers interlockin with the drilling elements to hold same in p ace.

In testimony whereof, I have signed my name to this s ecification.

C RLES B. KENNEDYE. 

